Monday, December 7, 2009

Web Shells

In PHP, ASP, JSP, Perl, And ColdFusion

Web shells come in many shapes and sizes. From the most complex of shells such as r57 and c99 to something you came up with while toying around with variables and functions. This paper is to discuss ways of uploading and executing web shells on web servers. We will discuss web shells for: PHP, ASP, Java, Perl, and ColdfFusion. A lot of these sections look the same because they are essentially the same. In a broad generalization of things, exploiting java is no different from exploiting Perl - we're watching certain variables and functions. The main emphasis of this paper however will be on ASP and PHP as they are the most common languages used in web applications today. We will also discuss how I've been able to place web shells on web servers in each language, as well as provide vulnerable code to look for to aid on placing a web shell on the box. With that said, lets get this show on the road!